Mechanical movement



NOV 11 1952 B. o. PRENTICE MECHANICAL MOVEMENT 3 Sheets-Sheet 1 FiledNOV. l, 1949 INVENTOR @EARL o- PRENTICE BY 'mmfP/A H Ay Ill.. llllllll/ww Wmmwwwumw@ UNH -HIL MMWWWMMWWWMWNNWJ (C. 1111 l ATTORNEYS Newn 11,1952 B. o. PRENTICE MECHANICAL MOVEMENT 3 Sheets-Sheet 2 Filed NOV. l,1949 www INVENTOR- BEARL O PRENTICE BY @www #(22245 ATTORNEYS Nov.. 11,1952 B. O. PRENTICME MECHANICAL MOVEMENT 3 Sheets-Sheet 3 Filed Nov. l,1949 m, w @m ON O:

BEARL 0- PRENTICE ATTORNEYS Patented Nov., 11, 1952 UN 11T D Claims.

The present'inventionrelates Ato improvements in mechanical movementsadaptedto-holding;v

turning, clamping, cutting-forming g and otherY force applying or,resisting mechanism.

MoreV specically, the principles herein disclosed find particularV usein clamps,l vises,v

wrenches, pliers, work-holders, fixtures, jigs,` chucks, shears,cutters4 andsimilar tools and de-Y vices,.as well as in the broader eldof push andpull mechanisms.

When mechanism is providedtogposition one. member relative to anothertoclamp, hold, twist;

turn, cut or form the parts .betweenjthe mem;- bersif relativerigidityis to be maintainedwith adjustability to parts ,of varioussizes-provided; a

screw is usuallyernployed'in mechanical linkage. with wedges, cams andeccentrics less fremiently'vk used. Incombination with the screw orequivalentmeans is frequently employed toggle joints,

the Aadjustability and rigidity of the screw.

As an example of-theprior artias appliedito' wrenchesand4 pliersreference may` be'. hadjtov thePeterson Patents-Nos. 1,489,458 and2,481,866,`

Whereinadjustabilityto'parts of diiie'rent sizesy is obtained by manualadjustment of a screw abutment which locates .the-position ofthetogglejoint fulcrum.

The Merriman Patent No. 2,439,483is another,

example of theprior-art in which theV necessity for adjustment tovarious sizes of parts has been provided by a manuallyradjustable'screw.

It isan, object of the. present invention to 4p roand mechanismsoutlined in the. opening paraf graph of thisspecic'ationtc provideautomatic leversof variousclasses, andcams to providej` quicker actingmechanism, while maintainingl sizing and adjustment to the part orsubject upon.,

which the device orA mechanismis to operate.

Another object of the invention is to provide mechanical movements forautomatically locat. ing the fulcrum of a toggle joint or itsequivalentn asa preliminary sizing or adjustment operation.

Another'object ofthe` invention is .to provide;

incombination with a., mechanical `.advantageA mechanism of -xed stroke,an automatically sizing abutment whereby substantially equalv iorcevor.resistance may be applied under varyingcon-v ditions of Y sizes,shapes, clearances, degrees ci wear and thevlike of the part orthedevice which-A may be the subject of the mechanical advantage aforcexapplying mechanism yembodying a-toggie i fulcrum at a pointwherebygthe,togglejjointfun..

tions in itslrange of maximum l mechanical. ladr'. vantage.

Other objects and advantages, residing inthe.; combination, arrangementvand construction` of."k parts, willmore fully appearl fromabonsid'ertion of the following.,speciicationand,tlieapg,v pended claims.

Inthe drawings,

Fig. Iis aside elevationahviewpfa wrenchgon pliersembodying .the presentinvention and parte, ly ,shown in.- broken .crossesectiom i i Fig. II:is atop View of.-Fig.I,

Fig. III isa view of the.y construction shown pin., Fig. I, but'with the-jaWsin .the-full-yopened poe.A sinon,l

Fig. IV isa viewr similarf-toglig. Ifshowingfthegi jaws clamped-upona`fsmallobject vwith.;thefaut matic ffulcrumfpQlSitioning mechanism ,finftS; in i.- tial position-,,

Fig. V is 1 a` view similare tof` `Fig; IVfshmvingy,1` the position ofthe automatic1 fulcrum mecha nism'in .its fully applied; position;

Fig.y VI is a viewsimilarto Figf.IVi"showing.-.a.. part` of /larger size,l being clamped between the; jaws` and theV `automaticifulcrumpositioning:` mechanism in its :intermediate4 :state i. of 'Lopera---tion, and

Fig. VII shows Aa modiiiedf formJ of thedn-ven-l tion for adjustingtherstroke `oi -the toggle-1 joint# and the amount of progressive-sizing.-1

It is to be understood than,thefeonsrucnon-- shownin kthe drawing; 4inwhich' the A,principles ,of the present invention' have Vbeen appliedto, a wrench plier type, of tool vsolely for illustration, purposes. Itdoes represent,lhowever,oneQiOrmZ.. of the inventionupon which ,an`actualreduction. to practice has been -accomplishem ,Otheraandfmore.simplified construction.; embodyingqthey.. principles are anticipated;and fu nderconstract/101,11y

and will form the basis of continuing applications for Letters Patent.

Referring to Fig. I in which the position of the parts are shown withthe jaws closed upon themselves, or a very thin object, the sheet metalbody I of the tool is of channel shape to provide a xed handle portionI2 and a xed jaw supporting portion I4. Hinged on a rivet I6 is amovable jaw supporting member I8. Inserted jaws 20 and 22 are carried inthe parts I4 and I8 respectively.

Toggle linkage for actuating the jaw 22 relative to the jaw 20 comprisesa movable handle 24 having a hinged connection at one end with themember I8 through the rivet 26 with the other end 28 disposed along thehandle part I2. As shown, the handle 24 is sheet metal channel likeconstruction. The other link of the toggle takes the form of a member30, of substantial thickness having a hinged connection at one end withthe handle 24 through the rivet 32. At the other end, the member 30 hasa semi-cylinder portion 34 which hinges in the automatically adjustablefulcrum mechanism.

The automatically adjustable fulcrum mechanism comprising an abutmentrack 36 having teeth 38 on the one side and a projection 40 on the otherwhich presents a shoulder 42 to the turned in flanges 44. An opening 46in the channel of the handle I2 is provided for the projection 40 byturning up ears 48 from the iianges 44. A pin 50 inserted throughaligned holes in the projection 40 and ears 48 hold the rack 36 inposition.

Co-acting with the rack 36 is an abutment pawl 52 having teeth 54adapted to selectively engage the teeth 38 at different points along therack 35 depending upon the size of the object being clamped between thejaws 20 and 22. Along one edge of the pawl 52 is defined an ear 56 and achannel shaped fulcrum 58 each of which engage with the web 60 of thehandle I2.

Disposed between the pawl 52 and web 60 is a locking bar 62 axiallyslideable relative to the pawl 52. At one end of the bar 62 an outturned end 64 is provided to engage with and be actuated by the shifterplate 66 while at the other end a cam portion 68 is adapted to engagewith the portion of the pawl 52 to back up the engagement between theteeth 38 and 54. In the illustration, the bar 62 is narrower than thepawl 52 and slides in the channel fulcrum 58.

The end of the pawl 52 removed from the teeth 54 is shown of forkedconstruction defined by spaced portions 12 having transversely alignedslots 14. At the base of the forked construction is a sizing rackportion 16.

Supported in the fork of the pawl 52 for both axial and rotationalmovement is a sizing pawl 18. At one end of the pawl 18 is amulti-toothed pawl portion 80 adapted to selectively. engage upon axialand pivotal movement with the rack portion 16. The other end of the pawl18 has a socket portion 82 which in reality is the fulcrum of the togglejoint in that it provides the abutment bearing for the semi-cylinder end34 of the link member 30.

For controlling the movement of the sizing pawl 18 a catch 84 on thepawl 18 is engaged by a latch 86 hinged on a pin 88 carried on themember 30. A spring 90 urges the latch 86 toward the catch 84. Tendingto rotate the pawl 18 around the cylindrical end 34 of the member 30 andaway from the latch 86 is a spring 92 connected between the jawsupporting member I8 and a point of connection 94 on the pawl 18.

portion engaging the rack portion 16.

Operating in the slots 14 is a pin 96 carried in the end 34 of themember 30. The pin 96 has a free sliding t in the slots 14 to enable itto follow the angular shape of the slots which enable the pawl 52 tohave limited movement about the fulcrum 58.

The control for the locking bar 62 may conveniently take the form of athin metal plate 66 crimped on the member 30 by flanges |00 and locatedon the pin 96. An arcuate edge portion |02 has a turned ange with a slot|04 to receive the turned out projection |06 on the bar 62. It will beunderstood that as the angularity of the member 30 changes the bar 62will shift relative to the pawl 52.

When the handle 28 is swung into its wide open position as shown in Fig.III, the tension of the spring 62 swings the jaw supporting member I8into its wide open position and the pawl 52 has been positioned by thestop |08. This tension holds the pawl 52 against the stop |08 uponclockwise movement of the handle 28, as viewed in Fig. IV, while themember I8 is rotated about the pivot I6 until movement of the jaw 22toward the jaw 28 is resisted by some object I I0. This interrupts thearcuate movement of the pivot 26 with continued movement of the handle28 tending to straighten out the toggle. At this point the latch 82 isengaging the catch 64 and the cam portion I I2 located at one side ofthe projection |06 is between the stop 56 on the pawl 52, and the web60. As the pawl 52 is guided between the web 60 and the turned inflanges II4 o! the handle portion I2, the location of the pin 86 in theangular portion II6 of the slot 14 will result in the pawls 52 and 18and lock bar 62 all moving as a unit toward the right as viewed in Fig.IV.

As movement from the position of the pawl 52 in Fig. IV to the positionof Fig. V takes place. the change in angular position of the member 30results in the plate 66 shifting the bar 62 sufliciently t0 the right towithdraw the cam portion II2 from beneath the ear 56 to enable the pawl52 to rock about the fulcrum 58 bringing the teeth 54 into engagementwith the teeth 38 of the rack 36. As the movement of the bar 62 iscontinued the portion 68 will be disposed between the portion 10 of thepawl 52 and the web 60 to hold the pawl 52 in backed up engagement withthe rack 36.

Following the primary automatic location of the fulcrum mechanism forthe member 30 just described, continued movement of the handle 28 towardits closed position will bring the web II8 of the handle 28 intoengagement with the end |20 of the latch 86 to disengage the catch 84.Prior to such disengagement, the rocking of the pawl 52 about itsfulcrum 58 to engage the rack 35 as so aligned the slot 14 and pin 96 asto enable relative movement of the pawl 18 to take place between theforked end of the pawl 52. When the latch 86 disengages the catch 84,the pawl 18 is urged clockwise by the spring 92 into the position shownin Fig. V with the toothed The action of the pawl 18 lls in the spacebetween that portion of the pawl 52 engaging the rack 36 and thecylindrical fulcrum end of the member 30 supported, in the fulcrumsocket 82. Preferably, the portion 80 has a pitch over the length of itssurface approximately the distance between the teeth 38 of the rack 36.

It is to be understood that the primary positioning of the pawl 52relative to the rack 36 and the secondary positioning of the pawl 18relative toxtherraok 'I6 resultsiin the-automatic'nalflocationofrthe'fulcrum 82.for^the memb`er 30.; The Vtoggle jointis now established'ata point closev approaching theextend-ed portion of the toggle to take advantage of the full. power ofthe .toggle action as delivered from the handle 28 to the jaws 20 and22. The parts are shown in that position in Fig. V. Prior to movement ofthe handle 2B into-'position of Fig. I in which the pivot 32 has beenmoved slightly across the center of the toggle' joint as to be selflocking.

In Fig. VI the'manner in which the present invention adapts itself to alower part l I0 is shown. Itlwill` loe-noted thatthe pawl 52 has assumeda :position` vfurther to the right as compared to Figf...,V.. The bar.62. is shown .invan intermediate position'fwith respect tothe showingin Figs. IV!` and'V.

To understand the principle of operation of the construction abovedescribed, the pawl 'I8 may be considered in the nature of a wedge whichis rocked into position by the spring 92 upon being released by thelatch 86. From this point of view the engaging surfaces of the portion'I6 and 8e need not be toothed or otherwise roughened but may berelatively smooth. However, a toothed surface is preferred as itproduces an audible indication of the sizing operation upon slightoscillation of the handle 28 which results in the ful.-

crum 82 being moved slightly to the left with the f spring 92 ratchingthe tooth portion 89 over the rack 'I6 to ll in the space resulting frommovement of the fulcrum 82 to the left.

If it is assumed the teeth 38 are provided eight to the inch, thepositions the pawl 52 may assume are at least .125" apart. If the pitchof the toothed portion 80 over its arcuate surface is taken at .128" andsixteen teeth are provided, the advancement of a tooth on the portion 80over a tooth on the complementary rack i6 will result in the fulcrum 82being moved to the left approximately .008. After the handle portion 28has been moved to its innermost position to extend the toggle and exertthe force upon the jaw 22, if the handle portion 28 is slightly raisedor rotated counter-clockwise to move the fulcrum 82 to the leftapproximately .008, the spring 92 will ratchet the portion 80 over therack 16 one tooth which produces an audible click The greater thedistance the fulcrum 82 is moved to the left by slightly lifting thehandle portion 23, the greater will be the clockwise ratching movementof the portion 80 over the rack 18 within the limits of the .128 pitchin the case of the above example.

By exerting a pumping action upon the handle portion 28, of very slightamplitude, the jaw 22 may be advanced toward the jaw 20 with a step bystep movement applied with the full force of the toggle joint workingwith a range of movement directly adjacent the extended plane of thejoint. This characteristic of the invention following the initialautomatic sizing or location of the fulcrum 32 Well adapts the inventionfor use as cutters and shears, as for example, shear blades may beconveniently substituted for the jaws 20 and 22 to provide a heavy dutywire or bolt cutter.

Where it is desired to reduce the angularity between the hinge points ofthe toggle joint after the location of the fulcrum 82 has beenautomatically established, this may be done by changing the point atwhich the latch 86 is actuated to release the pawl 'i8 to complete theautomatic location of the fulcrum 82. One manner in which this may beaccomplished is shown in Fig. VII in which the latch 88 is equipped withan adjustable length" i proj ection' 1 86 fl'f Which zeng'ages'f. with.thee-,1 The projection 86", maytake th'e forms: of a screw whichk may,be:v threaded Vin Vand -olltptoiv catch 84.

vary the point .of releasefofthefcatch 84'.'

Where it is desired to adjust .the handle 23 from; anoverzcenter yinalpositionto a self .-opening position, the stop character of the centralportion'ofzf theA latch 86 through 'engagement l with :the Aweb ber86'." 'whichstraddles the latch fwithia'lsliding grip tov enable'it tobe manualli7 shifted-on' the memberSG" to engage the `web/I IG'., totheleft of the recessedportionofthe'hand1e28f tozstop;

thepaction-.offthe toggle y'short of the `ioverfcenter 5,.

position;

I'claim:

1. A mechanical movement structure for toggle joint mechanism forautomatically locating a fulcrum of the joint to vary the point ofextended position of the toggle to accommodate lthe joint to variousycondition-s of operation comprising a pair of links connected by apivot, an end of one of said links removed from said pivot being aforce-delivering end, an end of said :other of said links removed fromsai-d pivot being the fulcrum end of the joint, a xed abutment, amovable abutment mechanism hav-ing -a fulorum portion for the toggle towhich the fulcrum end o-f said other link is connected, means supportingsaid mechanism for longitudinal movement relative to said fixedabutment, mean-s connected to said mechanism to resist longitudinalmovement of said mechanism upon initial pivotal mo-vement of said linksin a toggle extending direction, yet capable of ybeing overcome by anincrease in resistance to movement of said force-delivering end of saidfirst link, interlocking parts upon said xed abutment and saidmechanism, and mechanism adapted to be actuated upon predeterminedmovement of said toggle joint to lbring said parts into interlockingposition yto form said abutment into a rigid composite abutmentstructure for said fulcrum.

2. A mechanical move-ment structure as dened in claim 1 wherein saidmovable abutment mechanism comprises a pair of relatively movablemembers one of which interlocks with said xed abutment, the other ofsaid member includes said fulcrum portion and is supported forengagement with said rst member upon relative transverse movement alongwedging surfaces.

3. A mechanical movement structure as dened in claim 1 wherein saidmovable abutment mechanism comprises a pair of relatively movablemembers. one of which nterlocks with said fixed abutment, the other ofsaid members includes said fulcrum portion and is supported forengagement with said rst member upon relative transverse movement alongwedging surfaces, and spring means continuously acting to increase thewedging action along said surfaces to extend said movable members tochange the vposition of said fulcrum portion.

4. A mechanical movement structure as defined in claim 1 wherein saidmovable abutment mechanism comprises a pair of relatively movablemembers, one of which interlocks with said xed abutment, the other ofsaid mem-bers includes said fulcrum portion and is supported forengagement with said first member upon relative transverse movementalong Wedging sur- 7, faces, spring means continuously acting toincrease the Wedging action along said surfaces to extend said movablemembers to change the position of said fulcrum portion, and means formoving said fulcrum portion in a, direction to permit said spring meansto increase the wedging action between sai-d members.

5. A mechanical movement structure for toggle joint mechanism as definedin claim 1 Wherein said movable abutment mechanism comprising a pair ofrelatively movable members, one of which interlocks with said xedabutment, the other of said members includes said fulcrum portion and issupported for engagement with said rst member with relative transversemovement along wedging surfaces, spring means continuou-sly acting toincrease the wedging action along said surfaces to extend saidrelatively movable members to change the posi-tion of said ful- 8 crumportion, means for moving said fulcrum portion in a direction to permitsaid spring means to increase the Wedging action between said members,said last means including an operating part of the toggle joint.

BEARL O. PRENTICE.

REFERENCES CITED The following references are of record in the iile ofthis patent:

UNITED STATES PATENTS Number Name Date 416,500 Robbins Dec. 3, 18891,445,280 Jordan Feb. 13, 1923 1,531,688 Bush Mar. 31, 1925 1,820,169Wigand Aug. 25, 1931 2,558,958 Jandus et al July 3. 1951

